Nullability Safety Playground

Try out -fnullability-safety, a proposed Clang flag for flow-sensitive null pointer analysis in C and C++

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Source Code

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Compiler Output

Nullability Safety ⓘThis Clang fork uses flow-sensitive nullability analysis and the selected pointer default. It runs as part of the normal compile — fast enough for every build and supported in clangd/IDEs.

Standard Clang ⓘStock-style Clang with flow analysis disabled and the type-based nullable-to-nonnull conversion warning enabled. It understands explicit casts but not control-flow narrowing.

Static Analyzer ⓘClang's built-in static analyzer (clang --analyze) with core.NullDereference and nullability checkers enabled. This is the tool people typically suggest for finding null bugs. It uses symbolic execution — slower and separate from the normal compile. It only catches nulls when pointers are explicitly compared to null or annotated _Nullable in the source.